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基于模糊控制原理,设计了利用单片机构成的模糊能耗制动服务梯控制系统,单片机AT89C51是该系统的控制核心.同时介绍了该系统的设计思想及其硬件结构
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High temperature corrosion tests in 75%Na2SO4-25%. NaCl molten salt have been conducted on waspalloy specimens plasma sprayed with Co-Cr-B-Si, Ni-Cr-B-Si-hCr3C2, X-40, X-40 + TiC and Ni/Al + Al2O3 coatings, test coupons were exposed isothermally at 750℃up to 200 h. After the corrosion tests, each sample was examined by OM, SEM and EMPA. It was found that X-40, X-40 + TiC and Ni/Al + Al2O3 were violently corroded by the molten salt due to cracking and spalling of the coatings, whereas Co-Cr-B-Si and Ni-Cr-B-Si + Cr3C2 exhibited superior corrosion resistance, which were thought to be related to the formation of chromium and silicon oxide film. A possible corrosion mechanism had been proposed and it is suggested that the excellent corrosion resistance and high hot-hardness of the two B-Si containing coatings may be of significance for applications in petroleum refining industry as
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The behavior of nitride inclusions during the VIM, VAR and ESR processes of superalloys has been investigated. The experimental results have proved that the inclusions in the original metals, even if the pure TiN power added rapidly decompose at the superalloy liquid processing temperature and the nitrides in the remelted metals are mainly precipitated from solution during the sulidification process
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Equilibrium between slag and molten iron at 1600℃ was investigated for the direct alloying of steel with Nb2O6-bearing slag. The activity of niobium oxide in the slag was measured. The αNb2O5 is in the range of 10-2-10-4. TheδNb2O5 is ranged in 100-10-2.Niobium partition decreases with the increase of[Si]% and CaO/SiO2. When α[0] and ΣFeO decrease, niobium partition decreases too. The δNb2o5 and the ratio of γsiO2 to γNb2O5 decrease with the incre-ase of slag basicity. The suitable thermodynamic conditions in direct alloying of steel with Nb2O5-bearing slag have been found
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In this paper the phase diagrams of LaCl3-LiCl and CeCl3-LiCl systems have been experimentally determined and theoretically calculated. Bath are simple eutectic systems. The eutectic points are at 25mol% LaCl3, 508℃ and 27mol% CeCl3, 494℃, respectively. The optimized phase diagrams and thermodynamical data of LaCl3-LiCl and CeCl3-LiCl systems with self consistency are a better basis for constructing ternary phase diagrams
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The Present work has found that the transverse rupture strength of WC-Co hardmetals can be improved by queuching heat treatment. The increment of transverse rupture strength (ΔTRS) was dependent on the cobalt content of hardmetal. The higher the cobalt content of hardmetal is, the more the increment of transverse rupture strength is. The main reason is that the transformation of face centered cubic cobalt stabilized at high temperature to hexagonal close packed cobalt can be depressed by quenching. The transformation temperature of hexagonal close packed cobalt binder phase was determined by differential thermal analysis. It was found that the transformation temperature increases with increase of cobalt content of hardmetal. The reason is that the cobalt binder phase of high cobalt hardmetal contains higher tungsten content than that of low cobalt hardmetal after quenching
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Using sand moulds for step-shape casting tests and different silicon percentage of nodular cast iron it was possible to separate structural variations produced during freezing from those occurring at Ac1 transformation temperature. The results show that an increase in silicon content leading to different variation in the matrix structure> leads to a changing mechanical properties of nodular cast irons. Tensile strength and elongation of obtained as-cast nodular cast iron with the composition of 3.9%C, 3.2%Si, 0.5%Mn are maximum of about 524.5N/mm2 and 19.8% accordingly. In the same nodular cast iron, but only with 0.1% Mn the silicon addition first increases after decreases elongation, impact toughness and hardness. But tensile strength changes to the opposite side
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西安石油大学外国语学院:《西方礼仪文化 Western Etiquette Culture》通识课程教学资源(电子课件,英文版)05.婚礼礼仪 The Etiquette at Wedding Ceremony
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Section A Premarital Agreements Section B Is the Traditional Family Structure at Risk? Section C A Male Nanny
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Section A A Good Heart to Lean On Section B The Right Son at the Right Time Section C Love of Life
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